In the 1980s, audiologists began cautioning lovers of loud music about hearing loss that could potentially result from use of their Walkman or portable compact disc (CD) players when those devices were on the cutting edge of music listening. With iPods the hot holiday gift for music lovers of all ages, Garstecki is encouraging safer use of the popular music listening devices.

"We're seeing the kind of hearing loss in younger people typically found in aging adults. Unfortunately, the earbuds preferred by music listeners are even more likely to cause hearing loss than the muff-type earphones that were associated with the older devices," Garstecki said.

Not only are earbuds placed directly into the ear, they can boost the sound signal by as much as six to nine decibels. "That's the difference in intensity between the sound made by a vacuum cleaner and the sound of a motorcycle engine," said Garstecki, professor and chair in the Roxelyn and Richard Pepper Department of Communication Sciences and Disorders.

In addition to the more intense sound signal, today's music listening devices -- with their longer battery life and their capacity to hold and conveniently play lots of music -- also encourage users to listen for longer periods of time than did the older portable devices. That, too, increases the potential for hearing damage, according to Garstecki.